Eventration of diaphragm is an abnormal elevation of diaphragmatic musculature while retaining normal attachments to the sternum, ribs and dorsolumber spine. It is a rare anomaly where the continuity of diaphragm remains intact. Pathological process can affect either all or only a portion of hemidiaphragm. Symptoms vary according to size of the defect. Large defect may mimic diaphragmatic hernia. The present case represents a full term female newborn that developed respiratory distress, cyanosis and feeding difficulties since 1st day of life. Clinical features and chest imaging of this case was assumed to be left sided diaphragmatic hernia which was found wrong in the operation theater. She was found to have left sided eventration of diaphragm to create symptom. Successful plication of ipsilateral diaphragm was done on 13th day of life. Supervised post operative ventilatory support along with other postoperative care improved the condition of this neonate. A large defect with eventration of diaphragm may be life threatening but a timely good management can save neonate from such condition.